The common basis of their life was the conviction that they enjoyed a new relationship with God, for which they were indebted to Jesus. The technical term for this relationship was “covenant,” and “covenant” became eventually in their vocabulary “testament.” Hence the later name for these writings of the church, when gathered into a sacred collection, was “The New Testament”—New because the older relationship of God to his people, which had obtained under Judaism with its Old Testament, was superseded by the faith and fellowship which Jesus Christ his Son had inaugurated. It was the consciousness of this that inspired the early Christians to live, and to write about the origin and applications of this new life. They wrote for their own age, without a thought of posterity, and they did not write in unison but in harmony.
Excerpted from A New Translation of the Bible: Containing the Old and New Testaments by James Moffatt (1870-1944), London: Hodder and Stoughton, 1935, New York: Harper, 1935, Introduction, p. xxii